supporting cache through use_trait

Gemfile

@@ -9,6 +9,8 @@ gem "json_pure"
 gem "sqlite3-ruby"
 gem "yard"
 
+gem "respondie"
+
 if RUBY_VERSION < "1.9"
   gem "ruby-debug"
 else

Gemfile.lock

@@ -72,6 +72,7 @@ GEM
       thor (~> 0.14.0)
     rake (0.8.7)
     rcov (0.9.8)
+    respondie (0.9.0)
     rspec (2.0.0.beta.19)
       rspec-core (= 2.0.0.beta.19)
       rspec-expectations (= 2.0.0.beta.19)
@@ -117,6 +118,7 @@ DEPENDENCIES
   rack-conneg
   rails (>= 3.0.0)
   rcov
+  respondie
   rspec-rails (>= 2.0.0.beta.19)
   ruby-debug
   sinatra

lib/restfulie/client/feature/cache.rb

@@ -1,7 +1,11 @@
 class Restfulie::Client::Feature::Cache
 
   def execute(flow, request, response, env)
+    Restfulie::Client.cache_provider.get([request.host, request.path], request)
     resp = flow.continue(request, response, env)
+    unless resp.kind_of? Exception
+      Restfulie::Client.cache_provider.put([request.host, request.path], request, response)
+    end
   end
 
 end

lib/restfulie/server.rb

@@ -1,3 +1,4 @@
+require 'respondie'
 require 'restfulie/common'
 
 module Restfulie
@@ -16,4 +17,9 @@ class ActionController::Base
   def self.restfulie
     include Restfulie::Server::ActionController::Base
   end
+
+  def self.use_trait(&block)
+    Respondie::Builder.new("Restfulie::Server::ActionController::Trait::$trait$", self).instance_eval(&block)
+  end
+
 end

lib/restfulie/server/action_controller.rb

@@ -2,11 +2,7 @@ module Restfulie
   module Server
     module ActionController #:nodoc:
       if defined?(::ActionController) || defined?(::ApplicationController)
-        autoload :ParamsParser, 'restfulie/server/action_controller/params_parser'
-        autoload :CacheableResponder, 'restfulie/server/action_controller/cacheable_responder'
-        autoload :CreatedResponder, 'restfulie/server/action_controller/created_responder'
-        autoload :RestfulResponder, 'restfulie/server/action_controller/restful_responder'
-        autoload :Base, 'restfulie/server/action_controller/base'
+        Dir["#{File.dirname(__FILE__)}/action_controller/*.rb"].each {|f| autoload File.basename(f)[0..-4].camelize.to_sym, f }
       end
     end
   end

lib/restfulie/server/action_controller/trait.rb

@@ -0,0 +1,10 @@
+module Restfulie
+  module Server
+    module ActionController #:nodoc:
+      module Trait #:nodoc:
+        puts "loading trait..."
+        Dir["#{File.dirname(__FILE__)}/trait/*.rb"].each {|f| autoload File.basename(f)[0..-4].camelize.to_sym, f }
+      end
+    end
+  end
+end

lib/restfulie/server/action_controller/trait/cacheable.rb

@@ -0,0 +1,81 @@
+class Expires
+  def do_http_cache(responder, headers)
+    if responder.options[:expires_in]
+      headers << "max-age=#{responder.options[:expires_in]}"
+      true
+    else
+      false
+    end
+  end
+end
+
+class LastModifieds
+  # default implementation that will check whether caching can be applied
+  def accepts?(responder)
+    responder.resources.flatten.select do |resource|
+      resource.respond_to?(:updated_at)
+    end &&
+      responder.controller.response.last_modified.nil? &&
+      !new_record?(responder)
+  end
+
+  def do_http_cache(responder, headers)
+    return false unless accepts?(responder)
+
+    timestamps = responder.resources.flatten.select do |resource|
+      resource.respond_to?(:updated_at)
+    end.map do |resource|
+      (resource.updated_at || Time.now).utc
+    end
+
+    timestamp = timestamps.max
+
+    responder.controller.response.last_modified = timestamp if timestamp
+  end
+
+  def new_record?(responder)
+    responder.resource.respond_to?(:new_record?) && responder.resource.new_record?
+  end
+
+end
+
+module Restfulie::Server::ActionController
+  module Trait
+    module Cacheable
+
+      CACHES = [::Expires.new, ::LastModifieds.new]
+
+      def to_format
+        headers = cache_control_headers
+        cached = CACHES.inject(false) do |cached, cache|
+          cached || cache.do_http_cache(self, headers)
+        end
+        if ::ActionController::Base.perform_caching && cached
+          set_public_cache_control(headers)
+          controller.response.headers["Cache-Control"] = headers.join(', ')
+          fresh = request.fresh?(controller.response)
+          if fresh
+            head :not_modified
+          else
+            super
+          end
+        else
+          super
+        end
+      end
+
+      private
+
+      def set_public_cache_control(headers)
+        headers.delete("private")
+        headers.delete("no-cache")
+        headers << "public"
+      end
+
+      def cache_control_headers
+        (controller.response.headers["Cache-Control"] || "").split(",").map {|k| k.strip }
+      end
+
+    end
+  end
+end